Improvement in steam-engines



2 Shseis--SheeLL 'Patented May.. 30,1871.

l'. W FORBES lmpovemant in Steam Engines.

All. fl/ora -L/r//os/*rAP/.f/c` m M x (05am/15's wmvfss) UNITED STATESline d din Fig. 1.

IsAAo- WILLIAM FORBEs, OE LA PORTE, INDIANA.

" lMPRovEMENT IN STEAM-ENGINES.

Specification forming part o f Letters Patent No. 115,301, dated May 30,1871.

. `To allwhom it mycooweru:`

\ `Be it known that I, IsAAc WILLIAM FORBES,

` of LaPorte, inthe county of La Porte and State of Indiana, haveinvented certain Improvements in Steam-Engines, of which the followingis a specification:v

The objectof the invention is to produce a steam-engine by means ofwhich a variable stroke of the piston-rod may be had, ifrequired, atleast in one direction. Such engines are used more especially indirect-acting quartzthevalve out at that line whilethis has it in.

Fig. 2 is a cross-section of the same cylinders,

las `viewed from `the top,"at dotted line a a in Fig. 5, with`everything removed out of the valve-seat. y Fig. 3is`a cross-sectionalview of the same cylinders, as viewed from the top, at dotted line c c-in Fig. 5, with everything removed out ofthe cylinders andvalve-chamber. Fig. 4 shows the cylinders and heads apart, ready forbeing bolted together, lookingat them internally` when-separated at thedotted Fig. 5 is a longitudinal central sectional view of this improvedsteamengine when used as fa stamp-battery with a portion Vof `the `frame`and the stamp-stems broken off, with the guide-plate through which thestamp-stems pass, with water-chamber un- `der .the stand of thevalve-stem for conveying water around eachstamp below thestufli 11g-boxand bearingoffthestamp-stems, aportion ofthe valve-stem and the valve`being removed from the valve-chamber, the induction-ports anddiffersfroni that shown in'Fig. 5, and may be used instead. Fig. 6is afull front view ofthe engine with a portionyof each sidelof the frametorn out, and the lower portion of the frame piston-rods and valve-stemsbroken oli". Fig. is a top view of 4the upper end of Fig. 6. Fig.

8 is a side view of Fig. 6 with a portion of the frame torn out vand thelower end broken olf. Fig. 9 is a bottom view of the lower head or headsof the cylinders when made in two pieces. Fig.`10 is across-section,'showing the method of coring out the cylinders so as toexhaust throughI the lower head, or it may pass around one cylinder andthen pass off. The sectional surface in. this figure is' `shown bydotted linee e in Fig. 11. Fig. 11 is a longitudinal central sectionalview of Fig. l0 with a portionof the frame attached, the lower portionbeing broken Oi'. Fig. 12 is a longitudinal central section of the sameengine, excepting in the method of taking in steam, and a slightvariation in the valve-frame,v and thedepth ofthe hole in the stemthrough which steam `passes from the feed-pipe to the valve. In thiscase` steam is taken in through the flange of the lower head (which iscastl together) of the valve-stem between the double stuffing-boxes.

This method is preferable to that described in previous figures.

General Description.

A A are cylinders. B B are valves. C is the valve-frame. Y Steam isreceived in the stem or frame of this fourfold valve and passes throughthe center of each valve-piece to its proper port, as the openin gsthrough the valves pass over the respective ports. D D and D2 D2 arecompanion-ports. D D lead to the upper end of'cylinder A. D2 D2 lead, atthe same time, to the lower end of cylinder A A'. Steam being takenin atthe upper end of cylinder A and the lower end of cylinder A', it willmove the piston of cylinder A down at the same time that the piston ofcylinder Al D1 D1 leading to the lower end of cylinder A,

while D3 D3 lead to the upper end of cylinder A and vreverses the motionof pistons; hence one piston is always being driven up while the otheris being driven down? To make this more complete when used as anautomatic direct-acting qu artz-battery the steam-passage through thevalve had better be on one side Enr EEICE.

of the center, next to the ports leading to the upper end of eachcylinder. E E are exhaustpipes. E1 is an induction steam-pipe. E2 E2 areexhaust-ports. F F is the thimble in the upper end of the valve, fittingthe valve-chamber and the valvestem; also, through which steam passes,through the induction steampipe, into the valve-stem and frame. F1 F1 istaper thimble iitting in the hole bored out in the upper head to receiveit. F2 is taper thimble iitting in the lower end of the valve-chamber atthe lower end of the cylinder, and which is also designed as a bearingfor the valvestem. As it wears it may be raised up by a set-screw orwasher, Src., slipped under, which will take up lost motion and form acomplete bearing. G is a taper plug designed to fit in the upper end ofthe valvestem, screwed down with an oil-cup in the top, through whichthe cylinders are oiled, and which also lits the taper thimble to fornian upper bearing for the upper portion of the valve-stem, designed toscrew down as it wears and take up lost motion. H H are pieces dressedup to form a steam-tight joint in their center, with groove and tongueupon one side, holding them in position while being bored out forstufngboxes, and itting their piston-rods, and turned oi at the upperend for iitting the lower portion of the piston and the piston-rod, andfilling the recess in the lower end of the engine, and turned ori' onthe outside to fill the holes which are bored out 'through the lowerheads to receive them. They are driven in their position after thepiston-rods are passed through the heads, forming a complete `joint asthough the head were of one piece, or they may be screwed in. Holes aredrilled in the joints between these pieces and the iianges in which theyare driven for receiving the studs of the glands of the stuffing-boxes.I is the valve-stein. J J are inclines or swells on the piston-rods andsta-mpstems. K K is the frame. L L, center plates or frame-work boltedto the frame, to which bearings are connected through which stamp-stemspass; M M, bearings, with glands and stufiing-boxes, their bearingsbeing in the glands, with waterchambers below for conveying waterthrough the channels around the stamp-stems for keeping the same cleanand supplying the battery below with water when wet crushing isrequired. W'hen dry crushing is required air or steam may be substitutedfor water. N is a bearing for the lower portion of the valvestem; also,a chamber which receives water for keeping the stamp-stems clean andsupplying the battery. O O, the upper head or heads of cylinders. O O',lower head or heads of cylinders. In Fig. 5', L is the guide-plate,varying from that in Fig, 5; P P, water-passages, cored out through theplate which passes through the frame and conveys water around thestamp-stem, and so in the battery; M1 M1, stuffing-boxes andwater-chambers, which are driven 'in plate L', and in which glands arescrewed for forming the bearing for the stampstems to work in. M2 M2 areglands. M3 M3 are chambers in the lower portion ot' stuiiingboxes, whichpass entirely around the stampstem, which convey water around the saine,and keeping it clean while not crushing, or, if dry crushing, air orsteam may be used instead of water to keep the dust out ot' the bearing.

When cylinders are cast solid, and it shall be found inconvenient todress the ports, the valve-seat may be bored out of sufficient area toreceive a thimble of sufficient thickness and strength, with portsdressed out to correspond with the valve and ports in the cylinder.

The glands d d are divided in the center so as to be slipped on thepiston-rods between the piston and swell, after the piston-rods havebeen put through the lower heads, when bands d d are shrunk upon theflanges ofthe glands, securely binding them and making them as oi' onepiece.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is- I l. 'Ihe ports D to I)3 for receiving andconveyin g steam to their respective cylinders at opposite ends, asdescribed.

2. The pieces H H, in combination with the lower heads O O',substantially as and for the purpose described.

3. The combination of the bearing M1, having a chamber, M3, and a gland,M2, substantially as described.

4. The plate L L and water-passage P P, substantially as set forth.

I. W. FORBES.

Witnesses:

W. H. FINCKEL, W. J. PEYTON.

